WEST SACRAMENTO – The tale of two whales stranded in the California delta has captured hearts and headlines in Northern California as efforts continued Friday to entice the injured mammals back to their salty home 90 miles west.

Along the dusty banks of the Port of Sacramento, hundreds kept tabs on the cetacean invasion while for the second day marine scientists aboard small boats played recorded sounds that included other humpback whales feeding.

But the wayward pair, a mother and her calf, showed no signs of cutting short their trip to the capital, and scientists said they won’t try to rush them, for now.

“We really do not want to stress the mother and her calf in any way,” said Frances Gulland of the Sausalito-based Marine Mammal Center, which is helping in the rescue operation.

If the underwater siren songs still don’t work, rescue coordinators planned to leave the whales alone this weekend to see if some downtime helps.

“We have been trying to do the most passive, least invasive tactics first,” said Carrie Wilson, a biologist with the California Department of Fish and Game.

Photographs showed the two were wounded during their travels, probably by a ship’s propeller, making it especially important to treat them with care, Gulland said.

Heavy boat traffic

Heavy weekend boat traffic in the delta is another reason to leave the whales alone for a few days, according to the U.S. Coast Guard.

“The port is the safest place for them to be,” said Ed Sweeney, a spokesman for the Coast Guard Auxiliary. “It’s a safety issue for both the whales and the public.”

The Coast Guard will enforce a 500-yard safety zone around the whales and the north Port of Sacramento channel. The boat ramp will remain closed to the public through the weekend.

Attempts to lure the whales back to the ocean with the recorded sounds are scheduled to resume Monday, when boat traffic eases, he said.

The whales briefly seemed to get the right idea by themselves Friday morning, when they headed 200 yards into the deep water channel leading to the Sacramento River, which eventually empties into San Francisco Bay. But then they turned around.

If there’s no progress by Tuesday, rescuers plan to start a herding operation, which would require at least 50 boats and include tactics such as banging pipes under water, a sound whales don’t like.

Friday, onlookers oohed and aahed – and clicked their cell phone cameras – as the whales occasionally broke the surface in a sibilant whoosh, their smooth gray bodies rippling through the placid waters.

Humphrey case

The scene was reminiscent of the publicity that attended Humphrey, a humpback whale that wandered into the delta – although not as far inland as the mother-calf duo – by way of San Francisco Bay more than 20 years ago. In Humphrey’s case, the whale was in freshwater for 26 days and suffered no ill effects.

Based on that experience, scientists are not overly concerned that the newly stranded whales are in immediate danger even though they have nothing to feed on, Wilson said.

“Maybe it’s not salt water, it’s not ideal, it’s not where they want to be, but they are safe,” she said.

The Sacramento whales probably were on their annual trip up the California coast to cooler waters up north when they got lost.

The whales have inspired a naming contest in local newspapers and television stations. Friday, Lt. Gov. John Garamendi, who has been helping coordinate news conferences at the port, announced that two names had stuck: Delta for the mother (because the whales are in the Sacramento-San Joaquin Delta) and Dawn for her calf – which Garamendi said referred to “a new day, a new hope, a new opportunity.”